Use Webdriver Manager for browser compatibility

Version mismatch between browser and selenium driver breaks the tests.
The Webdriver manager automatically ensures the compatibility by
downloading the right driver for the installed browser.

.gitignore

@@ -9,6 +9,9 @@ env/
 # IntelliJ project files
 .idea
 
+# Webdriver Manager: cache for selenium drivers
+.wdm
+
 # Generated (compiled) JavaScript code
 __target__/
 OOMAnalyser.js

Makefile

@@ -39,6 +39,7 @@ clean:
 	@find $(BASE_DIR) -depth -type f -name "*.pyo" -exec rm -f {} \;
 	@find $(BASE_DIR) -depth -type f -name "*.orig" -exec rm -f {} \;
 	@find $(BASE_DIR) -depth -type f -name "*~" -exec rm -f {} \;
+	@$(RM) --force --recursive .wdm
 	@$(RM) --force --recursive __target__
 
 #+ Remove all automatically generated and Git repository data

requirements.txt

@@ -1,2 +1,3 @@
 Transcrypt == 3.7.16
 selenium
+webdriver-manager

test.py

@@ -24,6 +24,7 @@ import threading
 import unittest
 from selenium import webdriver
 from selenium.common.exceptions import *
+from webdriver_manager.chrome import ChromeDriverManager
 import warnings
 
 import OOMAnalyser
@@ -84,7 +85,13 @@ class TestInBrowser(TestBase):
         server_thread.daemon = True
         server_thread.start()
 
-        self.driver = webdriver.Chrome()
+        # silent Webdriver Manager
+        os.environ['WDM_LOG_LEVEL'] = '0'
+
+        # store driver locally
+        os.environ['WDM_LOCAL'] = '1'
+
+        self.driver = webdriver.Chrome(ChromeDriverManager().install())
         self.driver.get("http://127.0.0.1:8000/OOMAnalyser.html")
 
     def tearDown(self):